Lens-grinding machine



May 19, 1925. 1,538,019 I C., L. BAUSCH LENS GRINDING MACHINE Filed Spt.1, 1921 3 Sheets-Sheet 1 IN VEN TOR.

6% mi! TTORNEY May 19, 1925.

C. L. BAUSCH LENS GRINDING MACHINE Filed Sept. 1, 1921 3 Sheets-Sheet 2v INVENTOR. fi'zrlmcfi 459A TTORNEY May 19, 1925.

c. L. BAUSCH LENS GRINDING MACHINE Filed Sept. 1,

1921 75 Sheets-Sheet 5 IN V EN TOR. L

. ATTORNEY Patented May 19, 1925.

UNITED STATES PATENT OFFICE.-

CARL L. BAUSCH, OF ROCHESTER, NEW YORK, AS'SIGNOR TO BAUSCH & LOMBOPTICAL COMPANY, OF ROCHESTER. NEW YORK, A CORPORATION OF NEW YORK.

LENS-GRINDING MACHINE.

Application filed September 1, 1921. Serial No. 497,560.

To all whom it may concern.

Be it known that I, CARL L. BAUsoH, of Rochester, in the county ofMonroe and State of New York, have invented certain new and usefulImprovements in Lens- Grinding Machines; and I do hereby declare thefollowing to be a full, clear, and exact description of the same,reference being had to the accompanying drawings, forming a part of thisspecification, and to the reference numerals marked thereon.

This invention has to do with grinding apparatus and relates moreparticularly to machines for grinding optical lens blanks to the desiredthickness, the chief object being to provide a simple and practicalmachine for conveniently and rapidly "grinding a portion of one side ofa lens to an accurately measured predetermined distance from theopposite side of the lens to form a mark serving as a guide in thesubsequent final grinding of the lens to the desired thickness. To theseand other ends the invention consists in certain improve ments andcombinations of parts, all as will be hereinafter more fully described,the novel features being pointed out in the claims at the end of thespecification.

In the drawings:

Figure 1 is a front-elevation of a machine embodying the presentinvention.

Figure 2 is a similar view showing the parts in a different position.

Figure 3 is a top plan view.

Figure 4 is an elevation as seen from the right in Figure 1.

Figure 5 is an enlarged sectional elevation on the line 5 5 of igure 3.

Figure 6 is a fragmentary detailed View of the lens holding device andcutting element in operation.

Figure 7 is a detailed View of a micrometcr part employed in themachine.

Figure 8 is a sectional view on the line 8"8 of Figure 5.

Figure 9 is a detail elevation of the lens holding device as shown inFigures 1 and 2, with a cover plate removed to expose the actuatingmeans.

Figure 10 is a detail view of one of the parts of the lens holdingdevice.

Similar reference numerals throughout the several views indicate thesame parts.

In the manufacture of optical lenses it has been a common practice,during the grinding of the lens to the desired thickness, to takemeasurements from time to time in order to ascertain when the lens blankhas been brought to the thickness desired. This has been a more or lesstroublesome factor in the operation for several reasons. It has requiredinterruption of the operation to make successive measurements of theblank. Furthermore, for the purpose of the grinding operation, the blankis usually fixed on a holder by an adhesive in a manner well known inthe art so that its edge or periphery only is accessible :formeasurement. As the thickness at the lens center is commonly differentfrom that at its edge portion, and as the center thickness is thedimension generally prescribed, ithas been necessary to calculate thecorresponding thickness for the lens edge portionin order to makethe'measurements. Not only has this consumed time and decreased the rateof production but the method, being of a more or less out and trycharacter, has resulted in inaccuracies and lack of uniformity in theresult. The present invention on the other hand provides apparatus forconveniently and, rapidly forming a'central mark or cut in one side ofthe lens extending to a distance from the opposite side equal to the.olesiredthickness"of the blank so that the latter is thus provided witha thickness indicating guide mark and may then be placed in the grindingapparatus and the surface ground away until the guide mark is reachedand the blank brought to the desired thickness. The machine of coursecomprises adjustable measuring or gage means to insure the accuratelocation of theguide mark, as more fully appears-from the followingdetailed description.

Referring more particularly to the drawings, the machine comprises aframe indicated generally at 15, Figures 1 and 2, having a base or bedportion 16 from which rise spaced bearings 17 and 18 for a shaft 19rotatably carried therein. The shaft is extended toward the right frombearing '18 over the bed portion of the frame and has fixed in anysuitable manner adjacent its end the grinding or cutting element 20.

The cutting element 20 is in the presentinstance in the form of acomparatively thin disk of any suitable abrasive material for .cutting agroove or kerf in the side of a lens to a depth 'suflicient to form atits bottom a guide mark indicating the amount to which the surface ofthe lens is to be ground away in a subsequent operation to reduce thelens to the desired thickness, it being understood that thepredetermined thickness is measured between the bottom of the cut thusmade and the opposite side of the lenses.

Shaft 19 supporting and rotating the cutting element may be driven byany suitable means, and in the present instance is provided between itsbearings 17 and 18 with tight and loose pulleys 21 and 22 for a beltdrive. A guard 23 is preferably provided for the cutting element and issupported on the adjacent bearing 18. :A pipe 24, Figures 2 and 5,carried byand extending upwardly from the guard serves as a means forsupplying the cutting element with a lubri cant which may be conductedto the pipe by means connected with its open upper end. 7 A lens holdingdevice, in which a lens blank may be conveniently gripped, carries thelens during the operation and comprises gage means in the form of ananvil for contact with ,the side of the lens opposite the cuttingelement. The gage means, or anvil, on which the lens rests, and thecutting element, are moved toward and from each 3 other with the lenslocated'therebetween and the degree of approach. of. these parts iscontrolled to mark the lens for subsequent grinding to the predeterminedthickness. It is obvious that either or both the gage means and cuttingelement may be moved for this purpose, thevmotion in the presentinstance being imparted to the gage means or anvil. v I

' As a support for the lensholding device the. frame bed 16. has fixedthereon a vertical standard or post 25, Figure 5, of cylindrical shapeon which slides vertically a sleeve 26 actuated by means presently to bedescribed. The lower end of the sleeve carries an arm 27 extending overthe bed of the machine, the outer end of the arm can ry ing the gagemeans or anvil comprising preferably a stud or post 28 the upper end ofwhich.is. finished with a convex gage surface for engagement with theunder side of the lens indicated at 29. On either side of the anvil 28sleeve 26 carries spaced.

parallel arms 30 and 31 which are relatively movable on the sleevetoward and from.

each other and provided with fingers or studs 32 for gripping the edgesof the lens or tracks 33, Figure 5, formed in a substantially channelshaped member 34 fixed on the sleeve. The inner end of arm 30 slides onthe lower track 33 and has a vertical extension 35, Figures 9 and 10, atthe upper end of which is a transverse slide or shoe 36 sliding in theupper track 33.

The other lens gripping arm 31 carries at its inner end a transverseslide or shoe 37, Figures 5 and 9, sliding in the lower track 33, andarm 31 is provided at the same end with a vertical extension 38, theupper end of which slidably engages the upper sur face of the uppertrack 33. As shown in Figures 5, 9 and 10, the vertical extensions 35and 38 of arms 30 and 31 respectively, are each in the form of arelatively thin plate disposed forwardly of and clearing the shoe of theother arm. Arms 30 and 31 therefore are supported on tracks 33 forsliding movement toward and from each other for gripping with theirfingers 32 the peripheries of lenses of various shapes and sizes. Aspring 39 fixed at its ends to the under sides of arms 30 and 31 tendsto draw the same together to engage and hold a lens placed on the anvil28, and a convenient manually operable means is provided for separating.the arms when inserting or removing a lens comprising preferably a lever40 pivoted on astud 41 carried by the fixed channel member 34' betweenthe shoes 36 and 37. The opposite ends of lever 40 extend opposite theshoes and are slotted to loosely engage pins 42 carried by the shoes.Lever 40 carries a handle 43 extending beyond the end of channel member34 at the right hand side of the machine for convenient operation ofthelens gripping means, and it is apparent that the latter is adapted tosupport a lens with the center of one side resting on anvil 28. A coverplate or housing 43 fixed to the forwardly extending flanges of thechannel member 34 encloses these operating parts. 7 V

The means for sliding sleeve 26 vertically on standard 25 to move thelens holding device toward and from the cutting element comprises,preferably, a lever 44 slotted at its left hand end, Figure 2, for looseengagement witha stud 45 fixed in a boss 46, Figure 3, on hearing 17 ofthe frame. Lever 44 is formed with a forked portion indicated generallyat 48, Figure 3, the armsfof which embrace sleeve 26 and are formed withbearings 49 receiving trunnions 50 carried by the sleeve and forming apivotal connection between the latter and the lever. One of .the

arms of the lever is extended toward the right hand side of the machineto provide a handle 51. by the vertical movement of which sleeve 26 andthe lens holding device may be raised to bring the lens and disk 20 intocutting engagement with each other.

Means are provided for accurately cone trolling the degree of approachof the lens anvil and cutting element comprising preferably a micrometerdevice for adjusting the height to whichthe-anvil is raised by theraising of the sleeve '26. Such adjusting device may be incorporated inany suitable manner, being in the present instance carried at the upperend of standard 25 and serving as an adj'ustable stoplimiting the upwardmovement of-sleeve 26. As 'shown in Figure 5 theframe of the standardhas a threaded bore or'opening 52 in which is threadedly engageda stud53. Theouter end of bore 52-is enlarged and slidably receives thereduced lower end 55 of one of the micrometer parts 54 whichis slidablycarried on stud 53. The end 55 ofi part-54, Figure 7, is keyed "orsplined to-standard 25 so that it may slide verticallyin theopening inthe latter but is held against rotation, and this portion 55 is threadedas at 56 for engagement with a collar '57 disposed as shown between theupper end of standard 25 and a shoulder formed by the lower end of anenlargement 58 on the part 54. Portion 58 is also threadedforrengagement with a nut or collar 59'which is thusrotatably'adjustable on the part 54 and forms a stop for the upper endof sleeve 26. Part 59-1s beveled at its upper end as at 59 to provide asurface onwhich are markedi'the 'graduati'ons ofiascale 60 as shownlinFigure 3. The cylindrical .upper end of part 54 adjacent scale 59 'ismarked with :vertically spaced graduations of a scale 61 and with aver-- tical zero line 62. It" is apparent from this construction thatafter loosening stud 53, collar 57 may be turned or adjusted on part 54in engagement with the upper end of the standard to vertically adjustpart 54'and the zero of scale 61 to compensate for variations,forexample, in'the radius of the cutting element. After'adjustment bolt '53may be tightened to clamp the parts in place. Parts 58 and 59 with theircooperating scales thus constitute a micrometerdevice'by means of whichstop 59 may be accuratelyset for controlling or measuring the degree ofapproach'of the lens anvil and cutting element.

In "operation after adjusting micrometer parts 58, if necessa'ry,so thatthe zero ofthe micrometer device corresponds with contact between thelens anvil and-cuttingelement, micrometer part 59 is 'turnedaswellunderstood in the art to indicate the desired lens thickness. Bymeans of handle 43 the lens gripping fingers 32 are separatedand 'a lensplaced with its lower surface onthe top of anvil 28 after which releaseof handle 43 allows the fingers to grip the edges of the lens and holdthe same centrally on the anvil. With the cutting element in rotationhandle 51 is then raised -'to carry the lens into cutting engagementwith the element and the cuttingoperation continued until sleeve 26 isstopped 'by themicrometer device which limits theapproach of the anviltoward the cutting element whenthe latter has marked the lens at theproper distance from its opposite side.

its apparent from the "disclosure themachine is simpleycompactand'practical in construction. The parts are so designed and arranged asto afford convenience in 1 adjust-ment and operation and the lens blanksmay be quickly inserted'and removed and thus rapidly and accuratelyprovided with a guide mark facilitating the grinding of the same to thedesired thickness.

I claim as my invention:

1. In a'machinetor forming a thickness indicatingguide mark in a lensblank, the combination with a support, of acutting element in saidsupport, a lens holding'element comprising devices adapted to engage theedge of the lens on opposite sides thereof and yieldably urged incontact therewith and:opposed tosaid cutting element, a lens gageopposing said cutting element, a lever for moving one of saidelements'relatively to the other during the cutting operation,-a stopfor limiting the extent otthe'cutting opera tion, and means foradjusting the'stop.

2. In a machine for forming a thickness indicating guide'ma rk in a lensblank, the combination with a support, of a cuttingelementiinsaid'support, a standard a lens holding element opposed'tosaid cutting'element and slidably mounted on said standard, a lensgageon said holding element, a lever for moving said-lens holding elementupon said standard during the cutting operation, a stop normally spacedfrom said holding element-for limiting the extent ofthe cuttingoperation, and micrometer devices for adjusting-the stop.

3. In a machine for forming-a thickness indicati.ngguide mark in' a lensblank,the combination with a support, of a rotary cutting element insaid sup-port adapted to contact with one face of the lens, a lensholding element opposed tosaid cutting ele ment, including devicesyieldably engaging the peripheral edge of the lens and a membercontacting with the'face' of the lens opposite to that F engaged by thecutting element, means for 'movi'ng the holding element toward and fromthe cutting element to bring a lens blank on the holding element into engagement with the cutting element,stop devices for limiting the extentof movement of the holding element to limitthe cutting of saidblankto apredetermined thickness, and micrometer means "for adjusting said stopdevices.

4. In a machine for forminga thickness indicating guide markin a lensblank, the combination with a support, of arotarycutting element in saidsupport, a lens holding" element opposed to said cutting element, said Iholding element including a pair of movable grippers adapted for asliding movement one toward another to engage a lens between them and alens gage adapted to engage the side of the lens opposite the cuttingelement, means for moving said holding element to move the lens into thepath of the cutting element, and a stop for limiting the depth to whichthe lens blank is cut, comprising an adjustable member normally spacedfrom and in the path of said holding 3 cutting'engagement, andadjustable measuring means limiting the relative movement of said chuckparts and element for cutting a portion of the lens to a predeterminedthickness.

6. A lens marking machine comprising a rotary cutting wheel, a lensholder including an-anvil for the lens disposed opposite said wheel andspaced devices yieldably engaging the peripheral edge of the lens andmovable with'the anvil as a unit, means for moving said holder towardand from said wheel to bring the lens into cutting engagement with the\vheel and micrometer means limiting saidmovement of the holder forcutting a markin one side of the lens at a predeten mined distance fromits opposite side.

'7. Ina machine of the class described, the

combination of a frame, a standard thereon,

a support slidable on said standard, a cut- '1 ting element, a lensholding element cooperating with said cutting element, one of saidcooperating elements being mounted on the frame and the other on saidsupport for movement of one toward and from the other ItO bring the lensinto engagement with the cutting element, a stop on the standard forcontrolling the cutting of the lens to a predetermined thickness, andmicrometer devices for adjusting said stop.

8. The combination of a frame, a standard thereon, a support slidablycarried on said standard, a cuttingelement on said frame, gage means onsaid support provided with devices for holding a lens with one side incontact with said gage means, operating" means for moving said supportto bring the side of the lens opposite said gage means into engagementwith said cutting element, and a stop on said standard provided with A amicrometer adjustment for controlling the movement of said support tocut the lens to a predetermined thickness.

9. The combination of a frame, a stand- I ard thereon, a supportslidably carried on said standard, a rotary cutting wheel on said frame,an anvil on said support provided with means for holding a lens with oneside in engagement therewith, means for moving said support to bring theother side of the lens into cutting engagement with said wheel, and astop threadedly carried by said post and provided with a micrometer ad-'justment for controlling the degree of approach of said wheel and anvilfor cutting the lens to a predetermined thickness.

10. The combination of a frame, a standard thereon, a support slidablycarried on said standard, a rotary cutting wheel on said frame, an anvilon said support provided with relatively movable parts for gripping thelens to hold the latter with one side on said anvil, manually operablemeans for effecting relative movement of said parts to grip and releasea lens, manually operable means for moving said support to bring theside of the lens opposite said anvil into cutting engagement with saidwheel, and stop means provided with a micrometer adjustment forcontrolling the degree of approach of said wheel and anvil for cuttingthe lens to a predetermined thickness.

11. The combination of a frame, a support movably carried by said frame,a cutting element, a gage element cooperating with said cutting elementand provided with means for holding a'lens,/one of said cooperatingelements being mounted on said frame and the other on said support formovement of one toward and from the other to bring the side of the lensopposite said gage element into engagement with said cutting element, amicrometer part adjustably carried by said framefor adjustment tocorrespond with the relative positions of said cutting and gageelements, and a cooperating micrometer part adjustably carried'by saidfirst micrometer part to form a stop for said support for controllingthecutting of the lens to a predetermined thickness.

12. The combination of a frame, a support movable carried thereby, acutting element, a lens holding gage element, one of said elements beingmounted on said frame and the other on "said support for relativemovement to bring the side of a lens opposite said gage element intoengagement with the cutting element, a supporting and clamping studthreadedly connected with said frame, a threaded micrometer part movableon said stud, a nut threadedly engaging said micrometer part foradjustably positioning the latter relative to said frame, a secondmicrometer part threadedly connected with the i first in cooperationtherewith and forming a stop for said support for controlling thecutting of the lens to a predetermined thickness.

13. The combination of a frame, a rotary cutting element thereon, lensholding means comprising an anvil for supporting and positioningengagement With one side of a lens, a member on said frame channelled toform a plurality of guideWays, members slidable in said guidevvayshaving fingers for supporting engagement with the periphery of the lens,and means for holding said fingers in engagement With the lens, saidlens holding means being movable to bring the side of the lens oppositesaid anvil into engagement With the cutting element, and adjustablemeans limiting the degree of approach of said cutting element and anvilfor controlling the cutting of the lens to a predetermined thickness.

14. The combination of a frame, a rotary cutting element thereon, lensholding means comprising an anvil for supporting and positioningengagement With one side of a lens, a member on said frame channelled toform a plurality of spaced guideways, members slidable in said guidewayshaving fingers for supporting engagement With the periphery of a lens, alever pivoted on the frame between said members and having its endsconnected With the latter, means tending to hold said fingers inengagement Wit-h the lens, handle means on said lever for moving thesame and said fingers to receive and release the lens, said lens holdingmeans being movable to bring the side of a lens opposite said anvil intoengagement With the cutting element, and adjustable means limiting thedegree of approach of said cutting element and anvil for cutting of thelens to a predetermined thickness.

15. In a machine for forming a thickness indicating guide mark in a lensblank, the combination of a thin cutting disk, a slidably mounted lenscarrying device including a holder and an anvil thereon arranged tosupport a lens in a plane at substantially right angles to the plane ofthe disk and a pair of slidably mounted arms upon the holder havingupstanding fingers engaging the edge of the lens, a lever for moving theholder to bring the lens into cutting engagement With the disk, and stopdevices for limiting the movement of the lens holding device.

16. In a machine for forming a thickness indicating guide mark in a lensblank, the combination of a thin cutting disk, a slidably mounted lenscarried device including a holder and an anvil thereon arranged tosupport a lens in a plane at substantially right angles to the plane ofthe disk, said holder having arms slidably mounted therein and providedWith spring pressed means having gripping engagement With the lens, anda lever for moving the holder to bring the lens into engagement With thedisk.

17 A lens marking machine comprising a frame, a thin rotary cutting diskthereon, a standard on the frame, a support slidable on the standard, ananvil on the support for engagement With one side of a lens, relativelymovable members on said support for releasable engagement With the lensto hold the same on said anvil, a lever pivoted on the frame andconnected with said support for moving the same to bring a lens on saidanvil into tangential engagement With said disk, and micrometer meansforming an adjustable stop for said support for cutting the lens to apredetermined thickness;

CARL L. BAUSCH.

